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<A href="introduction6.htm">Debugging Tools for Windows (WinDbg, KD, CDB, NTSD)</A> &gt; <A href="debugger_reference.htm">Debugger Reference</A> &gt; <A href="debugger_commands.htm">Debugger Commands</A> &gt; <A href="kernel_mode_extensions.htm">Kernel-Mode Extension Commands</A> &gt; </div>
	<div id="winchm_template_title">!obtrace</div>
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	<div id="winchm_template_content"><div id="mainSection"><p>The <b>!obtrace</b> extension displays object reference tracing data for the specified object.</p>
<pre class="syntax"><b>!obtrace </b><i>Object</i></pre>
<h2><a id="Parameters"></a><a id="parameters"></a><a id="PARAMETERS"></a>Parameters</h2>
<p></p>
<dl>
<dt><a id="_______Object______"></a><a id="_______object______"></a><a id="_______OBJECT______"></a>       <i>Object</i>      </dt>
<dd>
<p>A pointer to the object or a path.</p>
</dd>
</dl>
<h3><a id="DLL"></a><a id="dll"></a>DLL</h3>
<table>
<tr>
<td>
<p><b>
          Windows 2000</b></p>
</td>
<td>
<p>Unavailable</p>
</td>
</tr>
<tr>
<td>
<p><b>Windows XP and later</b></p>
</td>
<td>
<p>
          Kdexts.dll
         </p>
</td>
</tr>
</table>
<p> </p>
<h3><a id="Additional_Information"></a><a id="additional_information"></a><a id="ADDITIONAL_INFORMATION"></a>Additional Information</h3>
<p>For more information about the Global Flags utility (GFlags), see the Windows Driver Kit (WDK) documentation and <i>Microsoft Windows Internals</i> by Mark Russinovich and David Solomon. </p>
<h2>Remarks</h2>
<p>The object reference tracing feature of Windows records sequential stack traces whenever an object reference counter is incremented or decremented. </p>
<p>Before using this extension to display object reference tracing data, you must use <a href="#Bookmark36">GFlags</a> to enable <a href="#Bookmark87">object reference tracing</a> for the specified object. You can enable object reference tracing as a kernel flag (run-time) setting, in which the change is effective immediately, but disappears if you shut down or restart; or as a registry setting, which requires a restart, but remains effective until you change it. </p>
<p>Here is an example of the output from the <b>!obtrace</b> extension:</p>
<pre class="syntax" xml:space="preserve"><code>kd&gt; !obtrace 0xfa96f700
Object: fa96f700        Image: cmd.exe
Sequence  (+/-)  Stack
--------  -----  ---------------------------------------------------
   2421d    +1  nt!ObCreateObject+180
                nt!NtCreateEvent+92
                nt!KiFastCallEntry+104
                nt!ZwCreateEvent+11
                win32k!UserThreadCallout+6f
                win32k!W32pThreadCallout+38
                nt!PsConvertToGuiThread+174
                nt!KiBBTUnexpectedRange+c

   2421e    -1  nt!ObfDereferenceObject+19
                nt!NtCreateEvent+d4
                nt!KiFastCallEntry+104
                nt!ZwCreateEvent+11
                win32k!UserThreadCallout+6f
                win32k!W32pThreadCallout+38
                nt!PsConvertToGuiThread+174
                nt!KiBBTUnexpectedRange+c

   2421f    +1  nt!ObReferenceObjectByHandle+1c3
                win32k!xxxCreateThreadInfo+37d
                win32k!UserThreadCallout+6f
                win32k!W32pThreadCallout+38
                nt!PsConvertToGuiThread+174
                nt!KiBBTUnexpectedRange+c

   24220    +1  nt!ObReferenceObjectByHandle+1c3
                win32k!ProtectHandle+22
                win32k!xxxCreateThreadInfo+3a0
                win32k!UserThreadCallout+6f
                win32k!W32pThreadCallout+38
                nt!PsConvertToGuiThread+174
                nt!KiBBTUnexpectedRange+c

   24221    -1  nt!ObfDereferenceObject+19
                win32k!xxxCreateThreadInfo+3a0
                win32k!UserThreadCallout+6f
                win32k!W32pThreadCallout+38
                nt!PsConvertToGuiThread+174
                nt!KiBBTUnexpectedRange+c

----  ----------------------------------------------------------
References: 3, Dereferences 2</code></pre>
<p>The primary indicators in the <b>!obtrace 0xfa96f700</b> display are listed in the following table.</p>
<table>
<tr>
<th>Parameter</th>
<th>Meaning</th>
</tr>
<tr>
<td>
<p><b>Sequence</b></p>
</td>
<td>
<p>Represents the order of operations.</p>
</td>
</tr>
<tr>
<td>
<p><b>+/-</b></p>
</td>
<td>
<p>Indicates a reference or a dereference operation. </p>
<p>
        +1 indicates a reference operation.</p>
<p>
        -1 indicates a dereference operation.</p>
<p>
        +/-
        n indicates multiple reference/dereference operations.</p>
</td>
</tr>
</table>
<p> </p>
<p>The object reference traces on x64-based target computers might be incomplete because it is not always possible to acquire stack traces at IRQL levels higher than PASSIVE_LEVEL.</p>
<p>You can stop execution at any time by pressing CTRL+BREAK (in WinDbg) or CTRL+C (in KD).</p></div></div>	
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